Meaning of ABC in English

ABC

ABC /ˌeɪ biː ˈsiː/ BrE AmE noun

1 . [singular] British English , ABCs [plural] American English the letters of the English alphabet as taught to children

2 . the ABC of something British English , the ABCs of something American English the basic facts about a particular subject:

the ABCs of your computer

3 . (the American Broadcasting Company) one of the national television companies in the US

4 . (the Australian Broadcasting Corporation) the national public television company of Australia

Longman Dictionary of Contemporary English.      Longman - Словарь современного английского языка.